The present invention relates to a circuit breaker of the type including a contact spring having a fixed end clamped into the switch housing and a free end provided with a movable contact which is arranged to cooperate with a fixed contact, the spring being biassed to urge the movable contact away from the fixed contact, as well as a switching rocker which acts on the spring and a release device responsive to a current overload.
In such a circuit breaker, the rocker is arranged to selectively move the spring into a contact closing position and is mounted in the breaker housing to be pivoted about an axis extending approximately perpendicular to the spring for movement between a breaker opening position and a breaker closing position. The release device acts to permit the spring to execute a contact opening movement independently of the position of the rocker.
In such switches, switching off should take place automatically, in dependence on the occurrence of an excess current, even if the switching rocker is being retained in its switch closing position, a trip-free release should be effected.